Electrical instrument contact



Dec. 11 1923.

M. c. COSGRAY ELECTRICAL INSTRUMENT CONTACT Filed July 18. 1921 N TUE a na 11 19 j 1,426,800

' em-ms STATES PAT NT OFFICE.

ELECTRICAL INSTRUMENT CONTACT. i w Application filed July 18, 1921. Serial No. 485,576.

To all whom it may concern: the positions of the parts containing in in- 55 Be it known that I, MARK C. COSGRAY, a ventio-n relative to the dial or face the citizen of the United States, and a resident instrument. of Sandusky, in the county of Erie and lin the figures indicates the face ofthe State of Ohio, have made an invention apinstrument. The instrument is provided pertaining to Electrical Instrument Conwith a pointer 2 that is rotated over the face 00 tact; and I do hereby declare the following of the instrument by suitable mechanism of to be full, clear, and exact description of the character well known in the art, for the invention, such as will enable others causing the pointer to indicate substantially skilled in the art to which it appertains to the-condition of a storage battery to which make and use the same, reference being had the instrument is connected. A flexible con- 65 to the accompanying drawings, and to the tact 3 is also carried by the arbor 4', which characters of reference marked thereon, causes the rotation of the pointer 2. The which form apart of this specification. contact 3 is made of thin sheet metal and My invention has for its object to promoves over the face of the instrument, and vide a means for closing and'opening a ciris preferably located below the pointer 2. 70

cuit through a delicately constructed and The outer end of the movable elastic con- Y relatively slowly operated element, wherein tact 3 is normally positioned a short discertainty of electrical contact will be assured tance from the face 1 of the instrument.

when the circuit is closed, and quick open- Such instruments are usually provided with ing of the circuit will be performed when round headed contacts that extend a shortv 7 it is opened, and thus arcing is prevented. distance above the face of the instrument The invention finds its greater advantage and so that the flexible contacts, as they are when used in connection with electricalslowly moved by the arbor of the instrumeasuring instruments having a needle ments, ride over the heads of the fixed conpoint that is rotated over the face of a dial, tacts, and thus establish connections with an wherein one or more circuits are closed and electric magnetic switch that controls the cir- I opened, according to the position of the cuits of the system in connection with which needle on the dia such as in meters known the instrument is used. By reason of the- 80 in the art as Sangamo meters. slow moving flexible contacts, arcing is The invention may be contained in inproduced as it approaches and leaves the struments of different forms and in instru fixed contacts of the instrument, and also by ments used for different purposes. To illus reason of the very slight friction and slight trate a practical application of my invendeflection of the elastic member electrical 6 tionil have selected a mechanism as-an exconnection is not always established. This ample. of structures containing my invenmay be due to dirt orto a coating of oxides tion, and shall describe it hereinafter. A of the metals of the elastic contacts and the structure containing my invention, and a fixed contacts. I

part of the instrument to which it is ap- By my invention the elastic member-is 40 plied, are illustrated in the accompanying caused to be deflected from its normal posi drawings. tion, and so that it will be distorted from In the drawings, Figure 1 illustrates the its normal position as it approaches the dial or face of a coulomb meter or an fixed contact, and thus increase the presampere hour meter, which is commonly used sure produced by reason of its greatlyin- 4V to indicate the approximate charges con creased deflection from itsnormal position tained in storage batteries, the instrument or shape. Also the contact is so: formed being connected in a circuit of the battery that the movable elastic contact is suddenly and the source of current supply used for released from the fixed contact'when the"- charging the storage battery, and also in movable contact is moved to either direc- 59 the circuit of the line that be tion from the fixed contact.

carried by the battery. Fig. 2 is an edge As shown in the figures, a body having v View of the dial of the instrument and of an inclined surface 5 is so located-that the ,the parts co ing in mention. Fig; 3.- inclined surface is in the path of the end is asoniew Mastic of the elastic member 3. It is also so located that the lower edge will be positioned between the face of the instrument and the end of the flexible contact 3, whereby the end of the elastic contact will be engaged by the inclined surface and raised as moves in one direction over the dial. The lower edge, however, is located at a position sufficiently remote from the face of the instrument to permit the flexible member to pass beneath the edge when the elastic memher is moved in the opposite direction.

The inclined surface 5 may be formed on or supported by anysuitable member, having its support outside of the circle described by the end of the elastic member 3. As shown, the inclined surface is located on an inclined flange 6 supported by the angular member 7 that may be attached to the face of the instrument by any suitable means, such as by the screws 8.

The upper end of the flange 6 extends over the end of thefixed contact 9. The fixed contact 9 has a flat surface that contacts with the lower. side of the movable elastic contact 3 and so as to form a relatively large contact area between the fixed contact and the movable contact. If desired, one end of the fixed contact may be located beneath-the upper end of the flange 6, as shown in Fig. 3. The fixed. contact 9 may be in the form of 'a flange supported at a distance from the face of the instrument much greater than the upper surface of the elastic contact 3 when the elastic con tact is in its normal position relative to the face of the instrument, and the contact surface of the fixed contact 9 is located a little more than the thickness of the elastic mem her 3 towards the face of the dial, than the upper end of the flange 6. 1 This will cause the elastic member 3, located on the fixed contact 9, to be held substantially in its deflected position while resting on the fixed contact 9, and when the flexible contact moves to either end of the fixed contact it will quickly drop to its normal position with reference to the face of the instrument. The movable contact may then continue in its movement, or it may swing pass beneath the fixed contact 9 and so as not to make contact with the fixed contact. If it moves clockwise and strikes or touches the underside of the flange 6, it will be carried towards the dial and finally passed beneath the lower edge of the flange 6, and its resiliency will cause it to return to its normal position relative tothe face of the instrument.

' The fixed contact is supported by a means which is preferably located on the outside of the circle described by the end of the flexible contact 3, such as by the angular portion 10 that is integrally formed with the flange 9. It may be securedv by any suitable means to the face of the dial,- and back and 1 an electric circuit may be connected therewith by or throngh any suitable means. Lclaim: Q r p 1. In an electric instrument a resilient it contact movable over the face of the instrimient and normally located in spaced relation with respect to the face of the instrument, means located in the path of the resilient contact for deflecting the contact from its normal positionrelative to the face of the instrument, a fixed contact for receiving the resilient contact from the said means and located at a distance greater than the normal position of the resilient contact from the face of the instrument.

2. In an electric instrument a resilient contact movable over the face of the instrument and normally located in spaced relation with respect to the face of the instrument, means located in the path of the resilient contact for deflecting the contact from its normal position relative to the face of the instrument, a. fixed contact for receiving the resilientcontact from the said means and located at a distance from the face of the instrumentthat is less than the distance of the portion of the deflecting means that causes the greatest deflect-ion from the face of the instrument, and greater than the dis tance of the normal position of the movable contact from the face of the instrument.

, 3. In an electric instrument a resilient contact movable over the face of the instrument and normally located in spaced relation with respect to the face of the instrument. a flange located in the path of the resilient contact for. deflecting the contact from its normal position relative to the face of the instrument, a fixed contact for receivingthe resilient contact from the said flange and located at a distance from the face of the instrument that is less than the distance of the portion of the deflecting flange that causes the greatest deflection from the face of the instrument, and greater than the distance of the normal position of the movable contact from the face of the instrument.

4. In an electric instrument a resilient contact movable over the face of the instrument and normally undefiected and located in spaced relation with respect to the face of the instrument, means located in the path .of the resilient contact for deflecting the contact from its normal position relative to the face of the instrument. a fixed contact located in aplane substantially parallel to the face of the instrument for receiving the resilient contact from the said means and located at a distance greater than the normal position of the resilient contact from the face of the instrument. v

5. In an electric instrument, a resilient contact movable over the face of the instrument and normally located in spaced relation with respect to the face of the inand the face of the instrument and at a strument, a flange located in the path of point greater than the distance of the northe resilient contact fordeflecting the contact mal position of the movable contact from 10 om its normal position'relative to the face the face of the instrument;

5 of the instrument, a fixed contact for receiv- In testimony whereof, I have hereunto ing the resilient contact from the said flange signed my name to this specification.

and located between the end of the flange MARK C. COSGRAY. 

